We've used Delta Education's Science in a Nutshell as part of our homeschool science curriculum for a while now. While I do like them, I can't give them an unqualified thumbs up.
The kits come with most of the supplies you need to perform the experiments. However, you must check the experiment ahead of time to make certain you have the other supplies needed. They aren't always simple items like tape & scissors.
I also recommend that you carefully check your kit when it is received. I ordered several kits. There were broken, missing, or expired parts in some of them. Delta Education was really good about replacing the parts, but it would have been hard to take care of it I hadn't check the kits until I was ready to use them.
The projects can be done by homeschool families, but all are written to be done by small groups in a class room. As homeschoolers, we've seen this before, so it's not a deal breaker. It's just nice to know that you may need to adapt some.
The projects and learning activities require parent involvement. Unless you have an older learner who is fairly self-motivated, plan on doing these along with your child.
If you want to use the work book, you have to make copies, which is a hassle. Individual workbooks aren't available. However, the book is spiral bound, so it's not difficult to make the copies.
The text/workbook organization is jumbled and confusing. It's not a straightforward approach. It is designed to be used by a teacher in a classroom. I can see that a teacher who plans on using something over & over, would put the time into figuring it all out. But, I want something easy to open up and use.
However, I do like the kits. The experiments are easy to do. My kids get excited when I pull one out.
There are plenty of supplies for more than one child to use the kit. The kits come with most of the hard to find parts and supplies.
I love that they come in nice, tidy, easy to store boxes. The boxes stack easily and are easy to move around.
We've used them to best success when I've set up a co-op or "summer science camp" with four girls. Even numbers are better since many experiments put the students into pairs.
Delta Science recommends these kits for grades 2-6, and I agree that this is a generally appropriate range.